I have been told by various GM's that you can "choose" to miss in combat but I can't find anything in the rules that says this. I mean it makes sense to me but of course there is no "rule" that says that you can decide to miss, unless I am missing it (no pun intended.)

I have also been told that you can choose to "roll a 1" on most (if not any) d20 die rolls. For example, to choose to fail a save or to go last in initiative order. Again, is there a "rule" that states this? An FAQ entry? Anything?

However, I don't think choosing to miss is something supported by the rules, because there are a variety of effects that specifically trigger off of a miss. If one could choose to miss, than it would auto-trigger those effects. (All the effects I can think of are bad for the person who misses, but that may not account for every example.)

Regarding your last point, you can choose NOT to save against a spell, but not to have a save that you choose to make be a 1. Functionally pretty similar, but different. Similarly, with initiative you can always delay until after everyone else (multiple people that wanted to do this doesn't have any resolution process) but you can't choose what your roll, whether it is a 1 or not. This is also similar, although it is actually different in some cases, if the mechanic was just 'you can choose a 1' rather than delay, if you had a positive initiative modifier and someone rolled really poor with a negative initiative modifier you would still go before them, with delay you can go after them even if they got a -10 initiative.

To add to what Saldiven said, the entire concept of a 'miss' is nonsensical unless you are trying to hit. If I am trying to not hit you, and I don't hit you, I didn't miss at all, I in fact hit exactly what I was trying to.

Well I can see some things.
You can choose to get hit (friendly touch spells) and you can choose to fail a save for a spell (friendly spells). And they may have extended it to more things, like being able to miss or whatever.

But in all seriousness, you can't choose to miss, but you can pretend to attack, functionally the same but doesn't trigger effects on attack or effects on miss. Perhaps a Perform (Act) roll if you want to make it look good.

Bluff seems more appropriate. Pretty sure that's called "feinting" in most cases.

Bluff might be the appropriate skill (although I could see acting in some cases) but this isn't exactly or necessarily a feint. A feint is a false attack attempting to cause a particular response in a defender. That may well not be the goal here, for example, if I am pretending to attack someone who is secretly my ally I am not trying to feint against my ally, I am trying to fool an observer.

In truth, bluff is more appropriate to the later then it is to feinting. I have always found it a little weird that 3.x/Pathfinder tied feinting with the ability to tell a convincing lie, rather than the ability to fight well. Feinting is usually a pretty integral part of fighting and many can do it well (in the real world) without any particular skill at lying and being able to lie convincingly doesn't really let you perform the complex martial action of a well executed feint. Of course the reason for this is that the mechanic was originally designed mostly as a means for a rogue (associated with lying) to be able to get a sneak attack.

Goal of acting is to entertain. Goal of bluffing is to deceive. If your swinging at someone in order to entertain an audience, thats a thing, but it's a diffrent thing from trying to fool onlookers into thinking your legitimately attempting murder.

I wouldn't allow you to choose to go last. Roll your initiative and you can delay your turn until you want to go unless something happens that forces your turn to happen. Like Bleed, ongoing damage (on fire, acid), constitution checks to stabilize, confusion, dominate, in the area of an ongoing spell effect, etc.

For Saves-

Just about every time a friendly caster casts a spell on you, you are choosing to fail your save. Unless there is a specific reason you cannot. Namely some class features force you to roll saves for all spells. And then there are those area evocation spells. Where rolling a one means you lose an item so you have to roll no matter what. If you are playing with those rules.

For attacks-

Again, unless there is a reason that you have to attack using all your might and strength, then just choosing to miss isn't something you should not be allowed to do. Dominate, Confusion, Rage, other ongoing spell effects, attacking with a firearm or aoe effect (especially splash) would force you to roll. Attempting to pull a fast one and make others think you are fighting your hardest should call for some sort of opposed check.

As for what you decide to do at the table, there is no reason you couldn't roll, pretend to look at your attack bonus, and then claim a lower attack value than your roll actually gives you. This could include damage rolls as well. But someone looking at your dice could call you out on it. And if you are in fact cheating, expect someone (DM or another player) to be upset with you.

sadly "the darkness" is not a valid target for Magic Missile.
I actually had a player just last November 2017 in the level 3-7 replayable scenario tell me, "I shoot the dark with a magic missile". LoL. Creepers!

So... the game model, ahem, models a to hit, not a to miss. So to not hit you can change targets to not the target you do not want to hit. <grin>

You can try to not hit someone in real life and still accidentally hit them. Trained martial artist have been knocked out in sparring and when practicing punch or kick combos.

In addition the game assumes you are trying to hit so that is what it covers.

Choosing to miss would be a houserule if it was allowed.

Things as such nonlethal damage exist for you when you don't want to harm someone. If you just want to trick the bad guy into thinking you are attacking an ally there are no rules for that either, but I would allow a bluff check to work.

If there is another reason for the pretend attack maybe other ideas can be suggested.

If you want to miss you don't attack.
If you want to pretend you are attacking but deliberately miss, then you need to Bluff those you are trying to hoodwink.
Easy. No rule necessary. Simple interpretation.

For initiative you can delay your turn and take up a new initiative order below everyone else.

You can not attempt to save from spells. But you cannot just take a 1.

Even if you cannot choose to miss, you could attack and not use any of your bonuses to hit including your BAB. For that matter I don’t think there is any reason you could not use a lower STR to hit so you could even take a penalty on your chance to hit.

Even if you cannot choose to miss, you could attack and not use any of your bonuses to hit including your BAB. For that matter I don’t think there is any reason you could not use a lower STR to hit so you could even take a penalty on your chance to hit.

The rules say what you add. They dont say you "may add" so you don't get to ignore bonuses.

Assuming it's to be used as a warning shot or something of the like, you could roll vs an AC 10 assuming you don't expect any other effects. If you want something more, then you are closer to the territory of maneuvers which would require CMB vs CMD rolls.

The issue is, it's only a feint if you intend to benefit from it. Feinting otherwise serves no purpose if you don't intend to follow up. The problem is the OP hasn't stated what specifically he asked the question for. Only that he wants to know if you can purposely miss.

power attack (although if you do accidentally hit its a bigger whoops) combat expertise, attacking with two weapons especially if you don't have the 2 weapon fighting feats and more so if your using two large weapons. Oh you could close your eyes that should give you a huge penalty.

Say someone has cast a charm or compulsion on you. You make the save. The caster says attack party member 2. If you want that caster to be unaware that you made the save, what would be your mechanism for making a false attack?

Option 1: roll Bluff as if it were a feint, though you aren't attempting to make party member 2 flat-footed. Could party member 2 end up really flat-footed? For a low charisma fighter with no ranks, this Bluff won't be very effective against some caster opponents, and it may actually work against your fellow party member. Against a party member with bad Wisdom + HD and bad Sense Motive, and with the opposing caster with good Wisdom + HD or good Sense Motive, this could go really bad though. The ally would think you are really attacking him/her, and the enemy caster would know to recast the charm on you [or whatever they would normally do next].

Option 2: some mechanic based on a simple static DC, similar to Aid Another. For a low charisma fighter with 5 BAB and some other +5 bonuses from stats or magic, rolling a 2+ on the d20 would get you what's needed to hit AC 10 under the aid.

[in essence, at a certain point, you succeed, unless you roll a 1]

Option 3: roll a d20; if you roll a 1-19, you succeeded in missing. On a 20 do it again, and if you have another 20, you just confirmed the critical against your friend, otherwise, it's normal damage against that friend [since 20 always hits, and there has to be some mechanism of risk in swinging near your friend in melee or shooting toward your friend at range].

[in essence, regardless of your skill, you succeed, unless you roll a 20]

For either 2 or 3, the parties involved should still get a Sense Motive check.

For an official rules answer, I think Option 1 is correct. You won't be damaging your friend, but the caster has a better chance to figure out what you are doing than your friend does (given how HD and ability score distributions are normally aligned).

Maybe you could roll a separate Bluff for passing a secret message; just the one word "Duck" would be enough, and pretty effective if you say it in a language your party knows and the caster does not or does not hear.

The original poster has vanished, which leaves us all just flailing about, speculating.

One method for attacking but missing is "I attack the invisible Tiny familiar I know is sharing the target's square." You have a 50% miss chance because you can't see the Tiny familiar, and even if you succeeded at that roll, your attack will miss regardless because there is no such Tiny familiar present. You are permitted to attack foes you cannot see, so this is pretty supported. There aren't rules for accidentally hitting someone else in the same square, so this should work.

Say someone has cast a charm or compulsion on you. You make the save. The caster says attack party member 2. If you want that caster to be unaware that you made the save, what would be your mechanism for making a false attack?

The basic magic rules provide that a caster knows if his target makes or fails a save (AOE excepted). There are feats and at least one spell (Enchantment Foil) to let you fake being subject to an Enchantment Spell, but just having Bluff skill won’t do it.

Say someone has cast a charm or compulsion on you. You make the save. The caster says attack party member 2. If you want that caster to be unaware that you made the save, what would be your mechanism for making a false attack?

The basic magic rules provide that a caster knows if his target makes or fails a save (AOE excepted). There are feats and at least one spell (Enchantment Foil) to let you fake being subject to an Enchantment Spell, but just having Bluff skill won’t do it.

It makes sense to be able to intentionally fail a will or reflex save as you could just not dodge the fireball and give into the entity trying to dominate you, but how do you intentionally fail a fort save? That would mean beings in the pathfinder universe have complete control of their immune systems and other automated processes.

Not the most outrageous oddity implied in the rules. Hell, lots of people believe it applies in real life, treating disease and illness as a battle where your personal dedication to survival is a vital factor in "winning the fight".